Backlight unit and display device including backlight unit

Abstract

A display device includes a display panel; a light source; a frame at a rear of the display panel; and a reflecting sheet between the display panel and the frame, the reflecting sheet having a rectangular shape with a first long side, a second long side opposite the first long side, a first short side adjacent to the first long side and the second long side, and a second short side opposite the first short side. Further, the reflecting sheet includes a first horizontal area along the first long side, and a first vertical area along the first short side. In addition, at least one of the first horizontal area and the first vertical area includes a first area including a plurality of first dots, a second area including a plurality of second dots and a third area including a plurality of third dots.

What is claimed is: 
     
       1. A display device comprising:
 a display panel; 
 a light source; 
 a frame at a rear of the display panel; and 
 a reflecting sheet between the display panel and the frame, the reflecting sheet having a rectangular shape with a first long side, a second long side opposite the first long side, a first short side adjacent to the first long side and the second long side, and a second short side opposite the first short side, 
 wherein the reflecting sheet includes a horizontal dot area along the first long side, and a vertical dot area along the first short side, 
 wherein the horizontal dot area includes a first horizontal dot area including a plurality of first dots, and a second horizontal dot area including a plurality of second dots, 
 wherein a size of the first dots in the first horizontal dot area is the same, and a size of the second dots in the second horizontal dot area is the same, and the size of the first dots in the first horizontal dot area is different from the size of the second dots in the second horizontal dot area, 
 wherein the second horizontal dot area includes the second dots arranged in at least two lines along the first long side, 
 wherein the vertical dot area includes a first vertical dot area including a plurality of first dots, and a second vertical dot area including a plurality of second dots, 
 wherein a size of the first dots in the first vertical dot area is the same, and a size of the second dots in the second vertical dot area is the same, and the size of the first dots in the first vertical dot area is different from the size of the second dots in the second vertical dot area, 
 wherein the second vertical dot area includes the second dots arranged in at least two lines along the first short side, and 
 wherein a width of the second horizontal dot area is different than a width of the second vertical dot area. 
 
     
     
       2. The display device of  claim 1 , wherein the frame includes a bottom and a sidewall extending from the bottom,
 wherein the reflecting sheet includes a first sheet part and a second sheet part extending from the first sheet part toward the sidewall of the frame, and 
 wherein the vertical dot area and the horizontal dot area are formed in the second sheet part of the reflecting sheet. 
 
     
     
       3. The display device of  claim 1 , wherein the vertical dot area has a different shape than the horizontal dot area. 
     
     
       4. The display device of  claim 1 , wherein the horizontal dot area further includes a third horizontal dot area including a plurality of third dots,
 wherein a size of the third dots in the third horizontal dot area is the same, 
 wherein the vertical dot area further includes a third vertical dot area including a plurality of third dots, and 
 wherein a size of the third dots in the third vertical dot area is the same. 
 
     
     
       5. The display device of  claim 4 , wherein the first horizontal dot area is closest to the first long side of the reflecting sheet, the second horizontal dot area is farther from the first long side of the reflecting sheet than the first horizontal dot area, and the third horizontal dot area is the farthest from the first long side of the reflecting sheet among the first horizontal dot area, the second horizontal dot area and the third horizontal dot area. 
     
     
       6. The display device of  claim 4 , wherein the first vertical dot area is closest to the first short side of the reflecting sheet, the second vertical dot area is farther from the first short side of the reflecting sheet than the first vertical dot area, and the third vertical dot area is the farthest area from the first short side of the reflecting sheet among the first vertical dot area, the second vertical dot area and the third vertical dot area. 
     
     
       7. The display device of  claim 4 , wherein the vertical dot area further includes a fourth vertical dot area including a plurality of fourth dots next to the third vertical dot area, and the fourth vertical dot area is the farthest area from the first short side of the reflecting sheet among the first vertical dot area, the second vertical dot area, the third vertical dot area, and the fourth vertical dot area. 
     
     
       8. The display device of  claim 7 , wherein a size of the fourth dots in the fourth vertical dot area is the same, and the size of the fourth dots in the fourth vertical dot area is smaller than the size of the third dots in the third vertical dot area. 
     
     
       9. The display device of  claim 7 , wherein an outermost width of the third vertical dot area is greater than a width of the second vertical dot area. 
     
     
       10. The display device of  claim 9 , wherein the outermost width of the third vertical dot area is greatest among the first vertical dot area, and the second vertical dot area, the third vertical dot area. 
     
     
       11. The display device of  claim 4 , wherein the size of the first, second and third dots in the horizontal dot area and the vertical dot area gradually changes in a direction from an outside of the reflecting sheet to an inside of the reflecting sheet. 
     
     
       12. The display device of  claim 4 , wherein a border line between the first horizontal dot area and the second horizontal dot area is straight, and
 wherein a border line between the second horizontal dot area and the third horizontal dot area is straight. 
 
     
     
       13. The display device of  claim 12 , wherein a border line between the first vertical dot area and the second vertical dot area is straight, and
 wherein a border line between the second vertical dot area and the third vertical dot area is straight. 
 
     
     
       14. The display device of  claim 4 , wherein the reflecting sheet includes another horizontal dot area along the second long side, and another vertical dot area along the second short side,
 wherein the another horizontal dot area includes another first horizontal dot area including a plurality of another first dots, another second horizontal dot area including a plurality of another second dots and another third horizontal dot area including a plurality of another third dots, 
 wherein the another second horizontal dot area is between the another first horizontal dot area and the another third horizontal dot area, 
 wherein the another vertical dot area includes another first vertical dot area including a plurality of another first dots, another second vertical dot area including a plurality of another second dots and another third vertical dot area including a plurality of another third dots, and 
 wherein the another second vertical dot area is between the another first vertical dot area and the another third vertical dot area. 
 
     
     
       15. The display device of  claim 4 , wherein a first distance between the first horizontal dot area and the first vertical dot area is shorter than a second distance between the second horizontal dot area and the second vertical dot area of the vertical dot area. 
     
     
       16. The display device of  claim 15 , wherein the second distance is shorter than a third distance between the third horizontal dot area and the third vertical dot area. 
     
     
       17. The display device of  claim 4 , wherein the width of the second horizontal dot area is a distance between a first horizontal middle line and a second horizontal middle line, the first horizontal middle line is a middle line between a center of the first dot closest to the first horizontal middle line in the first horizontal dot area and a center of the second dot closest to the first horizontal middle line in the second horizontal dot area, and the second horizontal middle line is a middle line between a center of the second dot closest to the second horizontal middle line in the second horizontal dot area and a center of the third dot closest to the second horizontal middle line in the third horizontal dot area, and
 wherein the width of the second vertical dot area is a distance between a first vertical middle line and a second vertical middle line, the first vertical middle line is a middle line between a center of the first dot closest to the first vertical middle line in the first vertical dot area and a center of the second dot closest to the first vertical middle line in the second vertical dot area, and the second vertical middle line is a middle line between a center of the second dot closest to the second vertical middle line in the second vertical dot area and a center of the third dot closest to the second vertical middle line in the third vertical dot area. 
 
     
     
       18. The display device of  claim 1 , wherein the horizontal dot area is located adjacent to the first long side of the reflecting sheet, and the vertical dot area is located adjacent to the second short of the reflecting sheet. 
     
     
       19. (orig  18 ) The display device of  claim 1 , wherein the first vertical dot area is closest to the first short side of the reflecting sheet, and the second vertical dot area is farthest from the first short side of the reflecting sheet, and
 wherein the first horizontal dot area is closest to the first long side of the reflecting sheet, and the second horizontal dot area is farther from the first long side of the reflecting sheet than the first horizontal dot area. 
 
     
     
       20. The display device of  claim 1 , wherein the second horizontal dot area includes the second dots arranged in a length direction of the second horizontal dot area and in the width direction of the second horizontal dot area, and
 wherein the second vertical dot area includes the second dots arranged in a length direction of the second vertical dot area and in the width direction of the second vertical dot area. 
 
     
     
       21. The display device of  claim 1 , wherein the width of the second horizontal dot area is a distance between a first horizontal border line and a second horizontal border line opposite to the first horizontal border line with respect to the second horizontal dot area,
 wherein the first horizontal border line is a middle line between a center of an outermost second dot in the second horizontal dot area and a center of a different size dot closest to the outermost second dot, the different size dot is disposed out of the second horizontal dot area, 
 wherein the second horizontal border line is a middle line between a center of an outermost second dot in the second horizontal dot area and a center of a different size dot closest to the outermost second dot, the different size dot is disposed out of the second horizontal dot area, 
 wherein the width of the second vertical dot area is a distance between a first vertical border line and a second vertical border line opposite to the first vertical border line with respect to the second vertical dot area, 
 wherein the first vertical border line is a middle line between a center of an outermost second dot in the second vertical dot area and a center of a different size dot closest to the outermost second dot, the different size dot is disposed out of the second vertical dot area, and 
 wherein the second vertical border line is a middle line between a center of an outermost second dot in the second vertical dot area and a center of a different size dot closest to the outermost second dot, the different size dot is disposed out of the second vertical dot area. 
 
     
     
       22. The display device of  claim 21 , wherein the outermost second dot adjacent to the first horizontal border line and the outermost second dot adjacent to the second horizontal border line are disposed in the width direction of the second horizontal dot area, and
 wherein the outermost second dot adjacent to the first vertical border line and the outermost second dot adjacent to the second vertical border line are disposed in the width direction of the second vertical dot area. 
 
     
     
       23. The display device of  claim 1 , wherein the width of the second horizontal dot area is a distance between a first horizontal border line and a second horizontal border line opposite to the first horizontal border line with respect to the second horizontal dot area,
 wherein the first horizontal border line is a middle line between a center of an outermost second dot in the second horizontal dot area and a center of a different size dot closest to the outermost second dot, the different size dot is disposed out of the second horizontal dot area, 
 wherein the second horizontal border line is a common tangent line of outermost second dots in the second horizontal dot area, wherein the width of the second vertical dot area is a distance between a first vertical border line and a second vertical border line opposite to the first vertical border line with respect to the second vertical dot area, 
 wherein the first vertical border line is a middle line between a center of an outermost second dot in the second vertical dot area and a center of a different size dot closest to the outermost second dot, the different size dot is disposed out of the second vertical dot area, and 
 wherein the second vertical border line is a common tangent line of outermost second dots in the second vertical dot area. 
 
     
     
       24. The display device of  claim 1 , wherein the width of the second horizontal dot area is a distance between a first horizontal border line and a second horizontal border line opposite to the first horizontal border line with respect to the second horizontal dot area,
 wherein the first horizontal border line is a middle line between an outermost second dot in the second horizontal dot area and a different size dot closest to the outermost second dot, the different size dot is disposed out of the second horizontal dot area, 
 wherein the second horizontal border line is a middle line between an outermost second dot in the second horizontal dot area and a different size dot closest to the outermost second dot, the different size dot is disposed out of the second horizontal dot area, 
 wherein the width of the second vertical dot area is a distance between a first vertical border line and a second vertical border line opposite to the first vertical border line with respect to the second vertical dot area, 
 wherein the first vertical border line is a middle line between an outermost second dot in the second vertical dot area and a different size dot closest to the outermost second dot, the different size dot is disposed out of the second vertical dot area, and 
 wherein the second vertical border line is a middle line between an outermost second dot in the second vertical dot area and a different size dot closest to the outermost second dot, the different size dot is disposed out of the second vertical dot area. 
 
     
     
       25. The display device of  claim 24 , wherein the outermost second dot adjacent to the first horizontal border line and the outermost second dot adjacent to the second horizontal border line are disposed in the width direction of the second horizontal dot area, and
 wherein the outermost second dot adjacent to the first vertical border line and the outermost second dot adjacent to the second vertical border line are disposed in the width direction of the second vertical dot area. 
 
     
     
       26. The display device of  claim 1 , wherein the width of the second horizontal dot area is a distance between a first horizontal border line and a second horizontal border line opposite to the first horizontal border line with respect to the second horizontal dot area,
 wherein the first horizontal border line is a middle line between an outermost second dot in the second horizontal dot area and a different size dot closest to the outermost second dot, the different size dot is disposed out of the second horizontal dot area, 
 wherein the second horizontal border line is a common tangent line of outermost second dots in the second horizontal dot area, 
 wherein the width of the second vertical dot area is a distance between a first vertical border line and a second vertical border line opposite to the first vertical border line with respect to the second vertical dot area, 
 wherein the first vertical border line is a middle line between an outermost second dot in the second vertical dot area and a different size dot closest to the outermost second dot, the different size dot is disposed out of the second vertical dot area, and 
 wherein the second vertical border line is a common tangent line of outermost second dots in the second vertical dot area. 
 
     
     
       27. The display device of  claim 1 , wherein the width of the second horizontal dot area is a distance between a first horizontal border line and a second horizontal border line opposite to the first horizontal border line with respect to the second horizontal dot area,
 wherein the first horizontal border line is a common tangent line of outermost second dots in the second horizontal dot area, 
 wherein the second horizontal border line is a common tangent line of outermost second dots in the second horizontal dot area, 
 wherein the outermost second dot adjacent to the first horizontal border line and the outermost second dot adjacent to the second horizontal border line are disposed in the width direction of the second horizontal dot area, 
 wherein the width of the second vertical dot area is a distance between a first vertical border line and a second vertical border line opposite to the first vertical border line with respect to the second vertical dot area, 
 wherein the first vertical border line is a common tangent line of outermost second dots in the second vertical dot area, 
 wherein the second vertical border line is a common tangent line of outermost second dots in the second vertical dot area, and 
 wherein the outermost second dot adjacent to the first vertical border line and the outermost second dot adjacent to the second vertical border line are disposed in the width direction of the second vertical dot area. 
 
     
     
       28. The display device of  claim 1 , wherein the reflecting sheet includes a central part and a side part between the central part and the four sides of the reflecting sheet, and
 wherein the horizontal dot area and the vertical dot area are only disposed in the side part of the reflecting sheet. 
 
     
     
       29. The display device of  claim 1 , wherein the reflecting sheet includes a central part and a side part between the central part and the four sides of the reflecting sheet, and
 wherein the side part is dots area including the first dots and the second dots and the central part is non-dot area. 
 
     
     
       30. The display device of  claim 1 , wherein each of the dot areas is defined by common tangent lines of outermost dots in each of the dot areas. 
     
     
       31. The display device of  claim 1 , wherein each of the dot areas is defined by all of the same size dots next to each other. 
     
     
       32. A display device comprising:
 a display panel; 
 a light source; 
 a frame at a rear of the display panel; and 
 a reflecting sheet between the display panel and the frame, the reflecting sheet having a rectangular shape with a first long side, a second long side opposite the first long side, a first short side adjacent to the first long side and the second long side, and a second short side opposite the first short side, 
 wherein the reflecting sheet includes: 
 a horizontal dot area including a first horizontal dot area, a second horizontal dot area and a third horizontal dot area along the first long side, wherein the first horizontal dot area is closest to the first long side of the reflecting sheet, the second horizontal dot area is farther from the first long side of the reflecting sheet than the first horizontal dot area, and the third horizontal dot area is the farthest from the first long side of the reflecting sheet among the first horizontal dot area, the second horizontal dot area and the third horizontal dot area; and 
 a vertical dot area including a first vertical dot area, a second vertical dot area, a third vertical dot area and a fourth vertical dot area along the first short side, wherein the first vertical dot area is closest to the first short side of the reflecting sheet, the second vertical dot area is farther from the first short side of the reflecting sheet than the first vertical dot area, the third vertical dot area is farther from the first short side of the reflecting sheet than the second vertical dot area, and the fourth vertical dot area is the farthest from the first short side of the reflecting sheet among the first vertical dot area, the second vertical dot area, the third vertical dot area, and the fourth vertical dot area, 
 wherein a size of dots in the first horizontal dot area is the same, a size of dots in the second horizontal dot area is the same, and a size of dots in the third horizontal dot area is the same, 
 wherein a size of dots in the first vertical dot area is the same, a size of dots in the second vertical dot area is the same, a size of dots in the third vertical dot area is the same, and a size of dots in the fourth vertical dot area is the same, 
 wherein the size of the dots in the first horizontal dot area is greater than the size of the dots in the second horizontal dot area, and the size of the dots in the second horizontal dot area is greater than the size of the dots in the third horizontal dot area, and 
 wherein the size of the dots in the first vertical dot area is greater than the size of the dots in the second vertical dot area, and the size of the dots in the second vertical dot area is greater than the size of the dots in the third vertical dot area. 
 
     
     
       33. The display device of  claim 32 , wherein the size of the dots in the fourth vertical dot area is smaller than the size of the dots in the third vertical dot area. 
     
     
       34. The display device of  claim 32 , wherein a width of the third vertical dot area is greater than a width of the second vertical dot area. 
     
     
       35. The display device of  claim 34 , wherein the width of the third vertical dot area is greatest among the first vertical dot area, the second vertical dot area, the third vertical dot area, and the fourth vertical dot area. 
     
     
       36. The display device of  claim 32 , wherein a width of the first, second and third horizontal dot areas is different from a width of the first, second, third and fourth vertical dot areas. 
     
     
       37. The display device of  claim 32 , wherein the frame includes a bottom and a sidewall extending from the bottom,
 wherein the reflecting sheet includes a first sheet part and a second sheet part extending from the first sheet part toward the sidewall of the frame, and 
 wherein the first horizontal dot area, the second horizontal dot area and the third horizontal dot area are formed in a horizontal part of the second sheet part, and 
 wherein the first vertical dot area, the second vertical dot area and the third vertical dot area are formed in a vertical part of the second sheet part. 
 
     
     
       38. The display device of  claim 32 , wherein a size of dots gradually changes from the first horizontal dot area, the second horizontal dot area and the third horizontal dot area in a direction from an outside of the reflecting sheet to an inside of the reflecting sheet, and
 wherein a size of the dots gradually changes from the first vertical dot area, the second vertical dot area and the third vertical dot area in a direction from an outside of the reflecting sheet to an inside of the reflecting sheet. 
 
     
     
       39. The display device of  claim 32 , wherein a border line between the first horizontal dot area and the second horizontal dot area is straight, and
 wherein a border line between the second horizontal dot area and the third horizontal dot area is straight. 
 
     
     
       40. The display device of  claim 26 , wherein a border line between the first vertical dot area and the second vertical dot area is straight, and
 wherein a border line between the second vertical dot area and the third vertical dot area is straight. 
 
     
     
       41. The display device of  claim 19 , wherein a shape of the first, second and third horizontal dot areas is different than a shape of the first, second and third vertical dot areas. 
     
     
       42. The display device of  claim 19 , wherein the second horizontal dot area is between the first and third horizontal dot areas, and the second vertical dot area is between the first and third vertical dot areas. 
     
     
       43. The display device of  claim 32 , wherein the second horizontal dot area includes the second dots arranged in at least two lines along the first long side, and
 wherein the second vertical dot area includes the second dots arranged in at least two lines along the first short side. 
 
     
     
       44. The display device of  claim 32 , wherein the second horizontal dot area includes the second dots arranged in a length direction of the second horizontal dot area and in a width direction of the second horizontal dot area, and
 wherein the second vertical dot area includes the second dots arranged in a length direction of the second vertical dot area and in a width direction of the second vertical dot area. 
 
     
     
       45. The display device of  claim 32 , wherein each of the dot areas is defined by all of the same size dots next to each other. 
     
     
       46. A display device comprising:
 a display panel; 
 a light source; 
 a frame at a rear of the display panel; and 
 a reflecting sheet between the display panel and the frame, the reflecting sheet having a rectangular shape with a first long side, a second long side opposite the first long side, a first short side adjacent to the first long side and the second long side, and a second short side opposite the first short side, 
 wherein the reflecting sheet includes a horizontal dot area along the first long side, and a vertical dot area along the first short side, wherein the horizontal area includes a first horizontal dot area and a second horizontal dot area, 
 wherein the first horizontal dot area includes multiple first horizontal dot lines, each of the multiple first horizontal dot lines including a plurality of first dots arranged in each of the multiple first horizontal dot lines, 
 wherein the second horizontal dot area includes multiple second horizontal dot lines, each of the multiple second horizontal dot lines including a plurality of second dots arranged in each of the multiple second horizontal dot lines, 
 wherein a size of the first dots in each of the first horizontal dot lines is the same, a size of the second dots in each of the second horizontal dot lines is the same, and the size of the first dots is different from the size of the second dots, 
 wherein the vertical dot area includes a first vertical dot area and a second vertical dot area, 
 wherein the first vertical dot area includes multiple first vertical dot lines, each of the multiple first vertical dot lines including a plurality of first dots arranged in each of the multiple first vertical dot lines, 
 wherein the second vertical dot area includes multiple second vertical dot lines, each of the multiple second vertical dot lines including a plurality of second dots arranged in each of the multiple second vertical dot lines, 
 wherein a size of the first dots in each of the first vertical dot lines is the same, a size of the second dots in each of the second vertical dot lines is the same, and the size of the first dots is different from the size of the second dots, and 
 wherein a number of the second horizontal dot lines is different than a number of the second vertical dot lines. 
 
     
     
       47. The display device of  claim 46 , wherein each of the dot areas is defined by all of the same size dots next to each other. 
     
     
       48. The display device of  claim 46 , wherein the size of the first dots in the first horizontal dot area is greater than the size of the second dots in the second horizontal dot areas, and
 wherein the size of the first dots in the first vertical dot area is greater than the size of the second dots in the second vertical dot areas. 
 
     
     
       49. The display device of  claim 48 , wherein the size of the dots in one of the multiple horizontal dot lines farthest from the first long side is smaller than the size of the dots in another of the multiple horizontal dot lines, and
 wherein the size of the dots in one of the multiple vertical dot lines farthest from the first short side is smaller than the size of the dots in another of the multiple vertical dot lines.